This Beautiful Classic 18H Director Trombone is in Great Playing Condition!Serial number dates this horn to 1958 (753,XXX), made in the USA!One of the more rare Coprian (100% pure copper) bell series that was made in the late 1950’s! See information pasted below this listing for more info on the history of Conn’s famous coprian bells!The hand slide has been lubricated and moves smooth and quick with little resistance!Tuning slide has been greased and pulls by hand!The Laquor is in amazing shape given its age with a little wear to the finish, and very minor dings/dents and scuffs as pictured!Classic shooting stars engraving on the bell looks great!All solder joints appear to be original and are rock solid!See pictures for best description!Vincent Bach Corp 15C mouthpiece included!Also comes with what appears to be the original hardshell case in Very Good condition!Has 2 working latches, handle, and both inner leather straps to secure the slide/accessories compartment!One of the plastic sliders that secures the bell at the brace has been replaced. Everything still sits safe and tight!All around Beautiful Trombone that has been well taken care of by previous owners, myself included.Listing includes trombone, mouthpiece, and hardshell case. Everything you need to start playing some tunes!Great for students, casual players, and collectors! SAME OR NEXT (BUSINESS) DAY SHIPPING!!!Now offering multiple shipping options!Here is some information from Conn I was able to dig up about this model:World’s first and only low priced trombone with famous seamless bell of Coprion!. Built in Bb with extra-fast, glassy smooth “Crysteel Airfloat” slides and long slide receiver for smoother action in 6th and 7th positions. Slide lock for added safety. Length 46″, weight 3 lbs. 3 oz., bell diameter 7″. What is Coprion?The process necessary for producing the Coprion bell was developed by Conn in 1938. It consists of electrolytically depositing COPper IONns (hence the name Coprion) onto a stainless steel precision form accurate to millionths of an inch (so Conn said in its 1959 catalog), creating a seamless bell. Coprion isn’t the same as a “rose brass” or “red brass” bell; these are brass bells with a higher copper content. Coprion is 100% pure copper. In its advertising for the Coprion bell, Conn showed diagrams of the structure of “ordinary” brass bells compared to the Coprion bell. The brass bell showed an “irregular and hodge podge” crystal structure with comparatively large crystals, while the Coprion bell showed “ions of pure copper side by side in regular, close knit conformation and at right angles to the surface of the metal”.What does Coprion do to the sound and the way the instrument plays?It is said that on an instrument with a Coprion bell “you can’t overblow or ‘crack’ a note.” Also, according to Conn, “Coprion has a special characteristic which permits great dynamic range without change in tone color.” It is generally accepted that high(er) copper content bells make the sound “darker” and have better projection. Jeff Stockham puts it well describing his 1959 10B Victor: “The copper bell also adds projection. This has been borne out by acoustical experiments done by Walter Lawson on french horn bells and by Cliff Blackburn on trumpet bells. Simply put, the high-copper-content bells direct a greater percentage of the energy expended by the player towards the audience, as measured in decibels. The sound of the instrument is less full behind the horn, to the player’s ear, but it is richer and louder in front of the horn — there is significantly increased directional projection. What this means to the player is this: 1) you need to exert less effort to produce a given perceived volume at any point in the performance hall, and 2) the sound remains darker and fuller without becoming shrill or breaking up at high volume levels. So with this 10B I can peel paint off the back wall of the hall if I feel like it, or blow a soaring solo line WITHOUT A MICROPHONE over the top of a screaming big band and still be heard.”The limited experience I have myself with Coprion bell instruments confirms this: it projects like nothing else, the sound doesn’t break up or become shrill at high volumees and you can really produce a lot of sound, and the tone color stays more or less the same no matter how loud you play.